9 research outputs found

    Localisation of nursery areas based on comparative analyses of the horizontal and vertical distribution patterns of juvenile Baltic cod (Gadus morhua)

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    Knowledge of the spatial distribution of juvenile cod is essential for obtaining precise recruitment data to conduct sustainable management of the eastern and western Baltic cod stocks. In this study, the horizontal and vertical distribution and density patterns of settled juvenile 0- and 1-group Baltic cod are determined, and their nursery areas are localised according to the environmental factors affecting them. Comparative statistical analyses of biological, hydrographic and hydroacoustic data are carried out based on standard ICES demersal trawl surveys and special integrated trawl and acoustic research surveys. Horizontal distribution maps for the 2001-2010 cohorts of juvenile cod are further generated by applying a statistical log-Gaussian Cox process model to the standard trawl survey data. The analyses indicate size-dependent horizontal and distinct vertical and diurnal distribution patterns related to the seabed topography, water layer depth, and the presence of hydrographic frontal zones (pycnoclines) as well as intraspecific patterns in relation to the presence of adult cod. The extent of the nursery areas also depends on the cod year class strength. Juvenile cod (≥3 cm) are present in all areas of the central Baltic Sea (CBS), showing broad dispersal. However, their highest density in the Baltic Basins is found at localities with a 40-70 m bottom depth in waters with oxygen concentrations above 2 ml O₂.l⁻¹ and temperatures above 5°C. The smallest juveniles are also found in deep sea localities down to a 100 m depth and at oxygen concentrations between 2-4 ml O₂.l⁻¹. The vertical, diurnally stratified and repeated trawling and hydroacoustic target strength-depth distributions obtained from the special surveys show juvenile cod concentrations in frontal zone water layers (pycnocline). However, the analyses indicate that in the CBS, juvenile cod of all sizes do not appear to aggregate in dense schooling patterns, which differs from what has been reported from the North Sea

    Franco-American Writers: In-visible Authors in the Global Literary Market

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    International audienceAs Armand Chartier concluded more than two decades ago, Franco American literature is on the boil (1991), yet, unlike other ethnic or postcolonial writers,1 Franco-American writers2 do not seem to be marketing ‘commodities’; they are rather the victims of an increasingly global market in cultural goods. And contrary to other writers from ethnic minorities, such as African Americans or Hispanics who can participate in the marketing of their marginality, they are scarcely in a position to participate in the marketability of Franco-American self-consciousness. Except for a handful of writers such as Jack Kerouac, Grace Metalious, Cathie Pelletier, Robert Cormier or David Plante, who are no longer considered as French Canadian or Franco-American when recognized on the literary market, and are mostly published by mainstream pub- lishing houses, most New England Franco-American writers operate on a regional scale and have found few venues for their works. As a matter of fact, the works of Camille Lessard Bissonnette, Gerard Robichaud, Denis Ledoux, Rhea Côté Robbins, Grégoire Chabot or Normand Beaupré have not reached such fame as to transcend their place of production. Franco-American literature is faced with yet another issue: i.e. classification or registration. Depending upon whether Franco-American writers write in French or in English, they obviously belong to different categories, which certainly partake in hindering their unity and visibility

    The Mucosal B-Cell System

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